Collapsible tubing with integral clamp



Aug. 20, 1963 l. N. JORGENSON COLLAPSIBLE TUBING WITH INTEGRAL CLAMP Filed Sept. 50, 1959 m m m m 3,101,20a coLrArsrnLE runner; wrrn INTEGRAL CLAMP Irving Nels Jorgenson, Grosse Pointe, Mich, assignor to The Wirenrold Company, West Hartford, Conn., a corporation of Connecticut Filed Sept. 30, 195?, Ser.-No.fl843,446 Claims. (Cl. 285-403) This invention relates to means to clamp the end of collapsible tubing to a duct or the like. More particularly, it relates to clamping means for collapsible two-element which could be made up or applied in the field as the tubing is cut into. required lengths.

Therefore, it is an object of this invention to provide a simple, economical and reliable clamping means integral with and formed from part of the tubing.

Another object is to provide clamping means having the aforesaid characteristics which can quickly be clamped or secured by pressure and released by unscrewing, when necessary. Y

Another object is to provide clamping means of the aforesaid type utilizing the existing structure of the tubing and requiring a minimum of easily carried-out forming operations and only one additional common and readily available element.

Other objects and advantages of the invention will appear as it is described in connection with the accompanying drawing.

In the drawing:-

FIG. 1 is a perspective view of one end or" collapsible tubing embodying the invention.

FIG. 2 is a diametrical section view through FIG. 1 looking from the interior of the tubing into the clamp.

.FIG. 3 is a broken side elevation view of the tubing of FIG. 1 shown embodying the invention at one end and prepared at the other for forming the new clamp.

FIG. 4 is an enlarged fragmentary end elevation View of the clamping screw and clamp of FIGS. 1 and 3.

FIG. 5 is a detailed longitudinal section view of adjacent convolutions of the tubing showing its structure.

FIG. 6 is a view similar to FIG. 4 of an alternate form of the invention.

Referring to the drawin the invention is illustrated in connection with two-element tubing of the type described in the A. E. Ohernack Patent 2,417,676 issued March 18, 1947 wherein a metal strip 10 is wound in the form of a helix with a flexible strip of fabric or plastic or other suitable material and connected to the edges of the adjacent convolutions of the metal strip. The edges l2, 14 of the metal strip are reversely bent and clamped between them and the body of the metal strip are the edges 22, 24 of adjacent convolutionsof the flexible strip. Since the metal strip is commonly of thin sheet metal which can be easily bent and formed into the desired shape, it lends itself readily to the bending and forming operations incident to creation of the clamp which will now be described. A

To form the clamp integral with and from the tubing itself, the tubing is cut through one convolution, A, of the metal strip parallel to the tube axis, such as along line xx of FIGURE 3, and across the flexible strip 20 up to the next convolution, B, of the metal strip. From that United States Patent 0 3,101,209 Patented Aug. 20, 1963 ice point, the flexible strip is then cutalon-g that edge of metalstrip convolution B which is nearest the convolution A for a short distance, such as up to the line y-y. The flexible strip is also cut in the opposite direction along said edge of the metal strip [for the :full peripheral distance around the convolution until the longitudinal out line x-.x is reached. The previous cutting of the metal strip and this cutting of the flexible strip completes the severing of the desired length of tubing from the supply.

The metal strip is'cut through the convolution B along the line yy and the flexible strip is cut back (from line yy to line xx. There are now free ends on the end convolution metal strip i.e., free end 16 between yy and xx (at the outer extremity) and free end 18 be- .tween x-x and yy at the inner extremity.

The opposite end of the severed length of tubing may be similarly cut through the two convolutions of the metal strip and through the flexible strip in the same manner.

The tube is'now in condition for formation of clamping means on each of its ends.

To form the clamp, the end 16 (FIGURE 3) of the end convolution A of the metal strip between cut-lines x-x and yy is folded upon itself in an inward direction and such folded end 16' is bent radially outward approximately at the cut-line yy.

Similarly, the opposite end 18 of said end convolution A of the metal strip is (folded inwardly upon itself and .that folded end 18' is bent radially outwardly approximately at line x-x.

"Dhe folded end 16' is then aligned 'with the folded end 18' by pressing the convolution A axially against convolution B until the portion of' convolution A adjacent the folded end 16' overlies convolution B. Preferably, but not necessarily the overlying portions of the convolutions 'will then be stapled together by a staple 19 passing through them at the overlap. The same may be done at the opposite end of the tube, length.

In order to draw the folded ends or tabs 16' and 18 together, and secure them in drawn or clamping position, holes are formed in each or the tabs '16, 18' in which is inserted a sell-tapping screw 17. By means of this selftappingscrew, the clamp may be tightened or loosened.

If the staple I9 is not used, the screw 17 will maintain the portion of the end convolution A of the metal strip adjacent the tab 16' overlapping the next convolution B of the metal strip.

In FIGURE 6, an alternative construction is illustrated. In this :form or the invention, instead of being out along line yy, the convolution A may be severed from the convolution B at a point midway between the lines xx' and yy (referring to FIGURE 4); and then by reversely Ibending that end of the convolution A, a tab 118 is formed as shown in FIGURE 6. Then, the short end: portion 01f the convolution B up to the line y-y (resulting tirom the nearness of the cut to line y-y, again referring to FIGURE 4) may be bent radially outward forming a single-leaved tab 118 (FIGURE 6).

Ilhe tab 116 may be made substantially like the tab 16, but more loosely bent so that when the outer end of the convolution A is moved over and upon the convolution B, the single-leaved tab 118 may interleave with parallel pants of the tab 116, all as shown in FIGURE 6.

The self-tapping screw may, as before, he passed through the tab 118 and then through the tab 116 including the tab 118 Since the tabs. 118 and 116 are thus kept aligned by the securing screw, it will not be necessary to staple together the ends of the convolutions A and B as was done in the previously described form.

In some instances, the thickness of the metal strip may enable all of the tabs in all forms of the invention to be single-leaved instead of reversely bent or double-leaved.

From the foregoing, it will be apparent that the invenmenses Q1) tion provides a clamp integral with the tubing and consisting of the last or outermost convolution of the metal strip and tabs or folded ends thereon. The clamp may be tightened or loosened by the turning of its securing screw. Because the clamp is integral with the tubing, it cannot be lost or separated from the tubing and it does not require any additional parts in its fabrication other than the common and easily procured securing screw.

Moreover, the clamp can be formed on tubing in the field or at any place by a fewsimple manipulations which can easily be performed by hand with commonly avahable tools.

Modifications within the scope of the invention will occur to those skilled in the art. Therefore, the invention is not limited to the precise form and detail of the invention as illustrated and described.

What is claimed is:

1. In combination with collapsible tubing comprised of a helically wound flexible stnip and a helioally wound metal strip with the edges of the metal strip reversely bent to clamp the adjacent edges of the flexible strip thereby interlocking said strips, clamping means integral with the tubing and constituted from said metal stnip, said clamping means comprising tabs bent radially outward from the metal strip adjacent the end and adjacent the start, respectively, of the end convolution of the metal strip, at least one of said tabs being formed as a foldedover and out-turned end of said end convolution, and means maintaining one end of said end convolution in overlapping relation to the next convolution of the metal strip.

2. In combination with collapsible tubing comprised of a helically wound flexible strip and a helically wound metal strip with the edges of the metal strip reversely bent to clamp the adjacent edges of the flexible strip thereby interlocking said strips, clamping means integral with the tubing and constituted from said metal strip, said clamping means comprising tabs bent radially outward from the metal strip adjacent the end and adjacent the start, respectively, of the end convolution of the metal strip, and means maintaining one end of said end convolution inoverlapping relation to the next convolution of the metal strip with said tabs substantially in register.

3. In combination with collapsible tubing com-prised of a helically Wound flexible strip and a helically wound metal strip with the edges of the metal stri reversely bent to clamp the adjacent edges of the flexible strip thereby interlocking said strips, clamping means integral with the tubing and constituted from said metal strip, said clamping means comprising tabs bent radially outward from the metal strip adjacent the end and adjacent the start, respectively, of the end convolution of the metal strip, tangentially extending means engaging said tabs for drawing them together, and means in addition to said tangential means maintaining one end of said end convolution overlapping said next convolution of the metal strip.

4. In combination with collapsible tubing comprised of a helioally wound flexible strip and a helically wound metal strip with the edges of the metal strip reversely bent to clamp the adjacent edges of the flexible strip thereby interlocking said strips, clamping means integral with the tubing and constituted from said metal strip, said clamping means comprising ta'bs bent radially outward from the metal strip adjacent the end and adjacent the start, respectively, of the end convolution of the metal strip, means formed from the next convolution of the metal strip to maintain a part of the end convolution of the metal strip overlapping said next convolution of the metal strip, and tangentially extending means engaging said maintaining means and engaging said tabs to draw said tabs together.

5. The combination as claimed in claim 4 in which maintaining means is a tab on said next convolution which is engaged by said tangential means and maintained in register thereby with said first-mentioned tabs.

References Cited in the file of this patent UNITED STATES PATENTS 560,610 Davidson May 19, 1896 582,646 Horn May 18, 1897 1,020,002 Warner Mar. 12, 1912 1,274,717 Hurley Aug. 6, 1918 1,358,550 Holnb Nov. 9, 1920 1,926,686 Newton Sept. 12, 1933 2,089,940 Brown Aug. 17, 1937 2,090,374 Olson Aug. 17, 1937 2,208,706 Spencer July 23, 1940 2,417,676 Chernack Mar. 18, 1947 2,522,684 Mitchell Sept. 19, 1950 2,697,452 Conroy et al Dec. 21, 1954 FOREIGN PATENTS 18,772 France Apr. 6, 1914 

1. IN COMBINATION WITH COLLAPSIBLE TUBING COMPRISED OF A HELICALLY WOUND FLEXIBLE STRIP AND A HELICALLY WOUND METAL STRIP WITH THE EDGES OF THE METAL STRIP REVERSELY BENT TO CLAMP THE ADJACENT EDGES OF THE FLEXIBLE STRIP THEREBY INTERLOCKING SAID STRIPS, CLAMPING MEANS INTEGRAL WITH THE TUBING AND CONSTITUTED FROM SAID METAL STRIP, SAID CLAMPING MEANS COMPRISING TABS BENT RADIALLY OUTWARD FROM THE METAL STRIP ADJACENT THE END AND ADJACENT THE START, RESPECTIVELY, OF THE END CONVOLUTION OF THE METAL STRIP, AT LEAST ONE OF SAID TABS BEING FORMED AS A FOLDEDOVER AND OUT-TURNED END OF SAID END CONVOLUTION, AND MEANS MAINTAINING ONE END OF SAID END CONVOLUTION IN OVERLAPPING RELATION TO THE NEXT CONVOLUTION OF THE METAL STRIP. 